HOW TO MAKE A NEST FOR A BUMBLEBEE

FIRST LET’S LOOK AT THE BUMBLEBEES’ LIFE CYCLE

SUMMER: Mature colonies produce new queens and the rest die out. New queens mate and most start hibernating in individual holes they dig in the ground.

AUTUMN: Some queens come out and start nests but most remain hibernating

WINTER: Queens hibernating. Some come out in late winter.

SPRING: Most queens come out of hibernation and start nests.

HOW BUMBLEBEES START NESTS IN NATURE

Queens search for sheltered places with insulating nest material such as a mouse, rat or rabbit nest in the ground. They make a small space inside the nest material, collect pollen and lay eggs on it. They also make a wax nectar pot. The diagram shows a queen nesting in a mouse burrow

Nesting materials:

1.  Jute felt. This used to be used as carpet underfelt. It may occasionally come available if a very old carpet is being replaced. But currently it is sold as a biodegradable mulch. Mitre 10 have “Jute Tex Bio Mat” Cosio brand,  which is $7.48/metre. You would need less than ¼ metre for one hive.

2.  Fibreglass insulation. Older style pink batts that can be teased apart work well (the newer type is bonded into a more structured block). The brown-coloured “Earthwool” brand is nicer to work with. These materials can be irritating and should be handled with dust masks and avoid getting fragments in your clothing. Insects are not affected by the fibrous dust.

3.  Sheep’s wool. Ideally should be short-fibre (a few cm) so it can be manipulated by the bumblebees. Long fibre wool can be cut shorter with scissors. Be careful if it is marketed as household insulation as it make contain insecticide to prevent moth damage.

4.    Hay and dead grass. Plain hay or straw is usually too stalky to be ideal but can be cut into shorter lengths of a few cm, and the coarser bits can be removed.

A sheltered place

Almost anything can work for this.

It should be

-           Dark inside

-           Sheltered from rain penetration

-           A volume of 2 – 4 litres

-           Somewhat porous or with ventilation gaps.

Options include:

-           Cardboard box. A shoe boxes are ideal because they have lift-off lids. If you use a standard carton with flaps it is best to fold the flaps down inside (which also strengthens it) and hand-fold a lift-off lid from cardboard cut from a larger box. Rain protection can come from taping sheet plastic (from a bag or polythene sheeting) over the top and a short distance down the sides. Carboard boxes are easily blown over so a weight such as a slab of wood on top is advised. Make a hole in one side about 15 – 25 mm diameter.

-           Wooden box. As above. Make a lid that lifts off, shoebox-style. They can be anything from 15 to 30 cm wide and high.

Section through a box with

Sawdust, dry earth or dead

leaves on the bottom. Folded-over

jute felt with a fluffed-up area

in the centre.

-           Coreflute box. As above. These can be made from recycled real-estate signs. The plastic is polypropylene which is difficult to glue, and ideally staple pliers can be used. Otherwise duct tape will hold. To get a good fold you need to groove the surface by scribing with a blunt screwdriver or similar tool.

-           Ground cavity. This is a pit, say 20 cm wide and deep, dug so a flat slab of wood, scrap concrete or paving slab can be placed over it. Dig a groove a few cm wide and deep so that there is effectively a tunnel from the edge of the cover to the cavity.

Positioning

While you would think a “warm” place would be good, direct sunlight can overheat these bumblebee boxes. They should be placed in dappled or complete shade. To reduce deliberate or accidental disturbance it is best to place them under shrubbery or in out-of-the-way corners behind buildings.

Adding animal scent

As bumblebees usually nest in disused animal nests, it seems likely that animal smells help them find them. If you have access to droppings of mice, rats (or probably guineapigs), or urine-contaminated litter, this may also be useful. Place some under or next to the nest material.

Hopefully you will attract a queen to make a nest. This can take awhile so just keep trying.

Here are photos of a shoebox nest we made.

Our grateful thanks to Nelson Pomeroy for these ideas.